Electric plug



July 10, 1934. a. v. WOODLING ELECTRIC PLUG Filed Dec. 30, 1930 Patented July 10, 1934 UNITED STATES.

PATENT OFFICE 15 Claims.

My invention relates to electric plugs and, more particularly, to electric plugs for appliances.

It is awell known fact that the pressure engagement, between the contact members of a plug for electrical appliances and the terminal members of the appliance, which is necessary to insure a good electrical contact, offers a resistance to theinsertion and the withdrawal of the plug. Consequently, because of this condition, the insertion and, more particularly, the withdrawal of the plug is very troublesome and annoy especially when the appliance is hot.

In order to alleviate the above described condition, an object of my invention is to provide for establishing a pressure engagement between the contact members of a plug for electrical appliances and the terminal members of the appliance to insure a good electrical contact and for reducing the pressure required for establishing such contact to facilitate the insertion or the withdrawal of the plug.

Another object of my invention is to provide for establishing a pressure engagement between the contact members of a plug for electrical appliances and the terminal members of the appliance and for controlling the current flow of the supply circuit by a common actuating member.

A further object of my invention is to pro Other objects of the invention will herein after become apparent.

This invention, accordingly, is disclosed in the embodiment thereof shown in the accompanying drawing, and comprises the features of construction, the combination of elements and the For a. fuller understanding OI-thBgQbjfiCtSiOf the invention, "reference. should ,be;had-tow;the following detailed description, taken? in 0011118073? tion. with .the accompanying, drawing inxwhich Fig. 1 is a plan view of a plug for 'electrical appliancesgembodying the'fea'tures oflmy inven- 1 tion; the upper part of th'eplug being removed to show the arrangement of the plug member's Fig.-2isaview,-' ross ectiom 'of-aj ug embodying the features of my invention, taken along the line IIII of Fig. 1.

Fig. 3 is a view, in cross-section, of a plug, embodying the features of my invention, taken along the line IIIIII of Fig. 1.

Fig. 4 is a perspective view of an actuating member utilized to actuate the contact members and the switching members.

Fig. 5 is an enlarged view, in cross-section, of the actuating member taken along the line V-V 85 of 4.

Fig. 6 is a perspective view of a switch member to which the supply leads are attached.

Fig. 7 is a plan view of a plug, embodying a modified structure comprising the features of my invention, the upper part of the plug being removed to show the arrangement of the plug members.

Fig. 8 is a perspective view of the parts utilized in such a plug as shown in Fig. 7.

Referring now to the drawing, 10 designates, generally, a plug housing having two parts held together by screws in order to facilitate the assembly of the plug members. As will be observed, the plug housing is provided with openings 12 and 13 in order that the terminal members of the appliance (not shown) will makecontact with the contact members 15 and 16 whe the plug is inserted on the appliance.

In order to facilitate the insertion and the withdrawal of the plug, the contact members 15 and 16 are constructed of two parts which are pivotally mounted on pins 17 and 18 and so disposed as to be actuated by a common actuating member 20 having cam members 23 and 24. As shown in Fig. 1, the actuating member 20 is rotatively mounted in the plug housing 10, and manually operated by a lever 25 mounted thereon. As preferably shown in Fig. 6, the lever 25 is mounted on the central portion of the actuating member, but it is apparent that, it may be mounted on an end, portion which is provided to extend through the side of the plug.

In operation when the actuating member 20 is rotated by moving the lever 25 forward, the rear ends 21 and 22 of the contact members" willso ride the cams 23f and 24: as -'t'o"e'stablish a: pr sure engagement to insuref 'g'ood' z electrical con tact'between the contactmemb'ers' 15a the terminaPmeiiibef's-oftheappli Ho'wever, wheii' the evfizsi trical contact, to facilitate the insertion or the withdrawal of the plug.

Inasmuch as it is desirable to prevent the current from flowing when the pressure engagement is reduced, switching means, actuated by the member 20, is provided. As will be observed, the members 23 and24, not only serve as cams to actuate the contactmembers 15 and 16 but also serve as switching members to control the current flow.

The cams 23 and 24, which are constructed of any suitable current carrying material, are so disposed on the actuating member that the circuit is closed when the pressure engagementis established to insure a good electrical contact and that the circuit is open when the pressure required for establishing such contact, is reduced. In order to provide for opening the circuit when the pressure engagement is reduced, the actuating member is formed of any suitable insulating material such as bakelite or hard rubber.

It is evident, any suitable means may be utilized to connect electrically, the cams 23 and 24, respectively, to the supply leads 30 and 31. As shown in Fig. 1, interconnecting members 33 and flange members 34 are provided, the latter of which being integrally formed with each of the earns 23 and 24. The members 33 are disposed around the actuating member 20 and intermediate the flanges 34 and the center portion of the plug.

As observed in Fig. 6, the members 33 are provided with a plurality of inwardly projecting contact fingers 36, in order that they may yieldingly maintain a good electrical contact with the flanges 34. The flanges 34, which are formed integrally with the cams, may be secured to the actuating member by any suitable means. Preferably, as shown in Figs. 4 and 5, they are moulded on the actuating members during the moulding process.

- For the purpose of securing the lever-25 in either the on or the off position and also for giving it a quick action when it is being moved from one position to the other, a spring 40 is provided. As shown in Fig. 3, one end of spring 40 engages an off-center notch 4l'provided on the lever and the other end engages a slot 42 provided therefor inthe center portion of the plug housing.

It is apparent from the foregoing description, taken in conjunction with the drawing, that other means may be utilized for actuating the contact members and the switching members, instead of the actuating member 20. As will be noted in Figs. 7 and 8, wedging members 45 and 46 mounted, respectively, on two interconnecting levers 48 and 49, are utilized.

The levers 48 and 49 are so pivotally mounted on the plug housing by means of pins 52 and 53 that the members 45 and 46 are actuated simultaneously when the lever 48 is operated. This is accomplished by connecting the inner ends ofv members 45 and 46 and project inwardly towards the members 54 and 55.

As will be observed in Fig. 7, the-fingers 50 and 51 are so disposed on the. wedge members 45 and 46 that the circuit is open when the pressure engagement is reduced, and closed when the pressure engagement is established between the contact members 15 and 16 and the terminal members of the appliance.

In order that the members 54 and 55 may be secured in their proper position, the ends thereof are so shaped as to extend into slots provided therefor in the plug housing.

For the purpose of securing the lever 48 in either the on or the off position and also for giving it a quick action when it is being moved from one position to the other, a spring 60 is provided. As shown in Figs. 7 and 8, one end of the spring 60 engages a notch 62 provided on the end of the lever 48 and the other end engages a slot 63 provided therefor in the side portion of the plug housing. 1

In operation, when the lever 48 is moved to the on position the spring 60 yieldingly urges the members 45 and46 to make wedging engagement with the ends 21 and 22 of contact members. In this position, the levers 48 and 49 are substantially in a straight line.

'in illustrated, since the structure may be considerably varied without departing from the spirit of the invention as defined in the appended claims.

I claim as my invention:

1. A detachable connector forelectrical devices having a terminal member comprising, in combination, a hollow body member, a contact member positioned in, and connected intermediate its end to, the hollow body member, one end of the contact member'being adapted to extend forwardly and engage a terminal member of an electrical device and the other end of the contact member being disposed to extend rearwardly for actuation, and means for operating the rearward end of the contact member and thus vary the pressure between the forward end of the contact member and the terminal member of an electrical device.

2. An electrical connector, in combination, a hollow body member, a contact member including two cooperative parts connected together intermediate their ends, the portion of the arts on one side of said connection being adapt to 5 form a receptacle and the portion of the parts 13 on the opposite side of said connection being disposed to form two spaced ends, a rotary member positioned between the two spaced ends, an interconnecting member, and a cam provided on the rotary member and electrically connected to the interconnecting member, said cam being disposed to actuate the two spaced ends and thus actuate the two parts of the receptacle relative to each other.

3. An electrical connector, in combination, a hollow body member, a contact member including two cooperative parts connected together intermediate their ends, the portion of the parts on one side of said connection being adapted to form a receptacle and the portion of the parts on the opposite side of said connection being disposed to form two spaced ends, an actuating member mounted to move intermediate the two spaced ends, an interconnecting member, a wedge provided on the actuating member and disposed to actuate the two spaced ends and thus actuate the two parts of the receptacle relative to each other, and a finger connected to the wedge for engaging the interconnecting member.

4. A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, a contact member positioned in, and connected intermediate its ends to the hollow body member, the portion of the contact member on one side of the connection being adapted to extend forwardly .and engage a terminal member of an electrical device and the portion of the contact member on the opposite side of the connection being disposed to extend rearwardly for actuation, a

' switch mounted in the hollow body member, and

means for operating the switch and for operating the rearward end of the contact member.

opposite side of the connection being disposed to extend rearwardly for actuation, a. switch mounted in the hollow body member, and a rotary member for operating the switch and for operating the rearward end of the contact member.

'6. A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, a contact member positioned in, and connected intermediate its ends to the hollow body member, the portion of the contact member on one side of the connection being adapted to extend forwardly and engage a terminal member of an electrical device and the portion of the contact member on the opposite side of the connection being disposed to extend rearwardly for actuation, a switch mounted in the hollow body member, and an actuating member having wedging means for operating the switch and for operating the rearward end of the contact member.

-'7. A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, a contact member positioned in the hollow body member and adapted to establish a pressure engagement with a terminal member of an electrical device, a switch mounted in the hollow body member, and means including a shaft supported by the hollow body member for operating the switch and for actuating the contact member relative to the terminal member and thus vary the pressure between the contact member and the terminal member.

8. In an electrical connector, in combination, a contact member including a portion adapted to form a receptacle and another portion disposed for actuation, a switch, and a common member for operating the switch and for actuating the actuation portion of the contact member to vary the opening of the receptacle, said actuation portion of the contact member being disposed to engage the common member.

9. A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, a contact member positioned in, and connected to, the hollow body member, the portion of said contact member in advance of the point of connection of the contact member and the hollow body member being adapted to engage a terminal member of an electrical device, a switch positioned in the rear of the said connection, and means disposed in the rear of the said connection and cooperatively associated with the contact member for actuating that portion of the contact member which is adapted to engage the terminal member of the electrical device, said means being operated in accordance with the actuation of the switch.

10. A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, engaging means positioned in the hollow body member for making an electrical contact with a terminal member of an electrical device, a switch positioned in the rear of the engaging means, and motion transmitting means for actuating the engaging means and thus varying the pressure engagement between the engaging means and a terminal member of an electrical device, said motion transmitting means extending rearwardly of the engaging means and being operated in accordance with the actuation of the switch.

11. -A detachable connector for electrical devices having a terminal member comprising, in combination, a hollow body member, engaging means positioned in the hollow body member for making an electrical contact with a terminal member of an electrical device, a shaft supported at a place in the rear of the engaging means by the hollow body member, a movable switch element controlled bythe shaft, a second switch element disposed to be engaged by the movable switch element, and means for connecting the second switch element to the engaging means.

'portion of the contact member, and means to transform movement of the switch operating element into movement of the movement transmitting means to move the movable portion of the contact member to cause the contact member to grip the contact pin. a

13. In an electrical connector, a hollow body member, a switch positioned in said body member and connected in the circuit of the connector, a contact member including a movable portion positioned in the hollow body member and having adjacent the forward end of the body member a por- 141) tion adapted to contact a contact pin, an operating element for the switch positioned rearwardly of the contacting portion of the contact member, movement transmitting means associated with the movable portion of the contact member, and 5 means to transform movement of the switch operating element into movement of the movement transmitting means to move the movable portion of the contact member to grip the contact pin.

and having a portion projecting therefrom 14. In a connector for electrical appliances, a hollow body member of generally rectangular form having an end face, a pair of relatively narrow lateral edge faces and a pair of relatively wide side faces, a pair of contact members positioned in the hollow body member and each having a socket extending longitudinally thereof adapted to receive the contact pins of an electrical appliance projected through an aperture in through an aperture in a lateral edge face of the hollow body and positioned rearwardly of the socket portions of the contact members mounted in said hollow body.

15. A detachable connector for electrical de- Y vices having a terminal member, said connector having a hollow body member, engaging means positioned in the hollow body member and having a socket portion for making an electrical contact with the electrical device terminal member, motion transmitting means associated with the engaging means and extending rearwardly of the socket portion thereof, means for operating the motion transmitting means and thus varying the pressure engagement between the engaging means and the terminal member, said means comprising a cam shaft rotatively supported by the hollow body member and positioned rearwardly of the socket portion of the engaging means.

GEORGE V. WOODLING. 

